From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030361Ab2GKWFy (ORCPT ); Wed, 11 Jul 2012 18:05:54 -0400 Received: from www.linutronix.de ([62.245.132.108]:35522 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030319Ab2GKWFW (ORCPT ); Wed, 11 Jul 2012 18:05:22 -0400 Message-Id: <20120711215612.161878327@linutronix.de> User-Agent: quilt/0.48-1 Date: Wed, 11 Jul 2012 22:05:20 -0000 From: Thomas Gleixner To: LKML Cc: Steven Rostedt , RT-users , Carsten Emde , Mike Galbraith , Theodore Tso Subject: [patch RT 6/7] fs, jbd: pull your plug when waiting for space References: <20120711214552.036760674@linutronix.de> Content-Disposition: inline; filename=fs-jbd-pull-plug-when-waiting.patch X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With an -rt kernel, and a heavy sync IO load, tasks can jam up on journal locks without unplugging, which can lead to terminal IO starvation. Unplug and schedule when waiting for space. Signed-off-by: Mike Galbraith Cc: Steven Rostedt Cc: Theodore Tso Link: http://lkml.kernel.org/r/1341812414.7370.73.camel@marge.simpson.net Signed-off-by: Thomas Gleixner --- fs/jbd/checkpoint.c | 2 ++ 1 file changed, 2 insertions(+) Index: linux-stable-rt/fs/jbd/checkpoint.c =================================================================== --- linux-stable-rt.orig/fs/jbd/checkpoint.c +++ linux-stable-rt/fs/jbd/checkpoint.c @@ -129,6 +129,8 @@ void __log_wait_for_space(journal_t *jou if (journal->j_flags & JFS_ABORT) return; spin_unlock(&journal->j_state_lock); + if (current->plug) + io_schedule(); mutex_lock(&journal->j_checkpoint_mutex); /*